Livestock such as poultry that are infected with pathogens, or serve as incubatory or convalescent carriers of pathogens, present problems both for the animals as well as humans who consume meat from the animals. Antibiotics are generally added to the nursery and grower feeds of poultry to promote growth and/or reduce disease occurrence during all phases of food production. The addition of antibiotics reduces the passage of pathogens such as S. Enteritidis to humans and has advantages for the health and weight of the poultry. Antibiotics promote growth through the reduction of biological stress, the decrease of bacteria, and by promoting the health of the poultry. Poultry that are healthy and disease free eat more food, and more effectively convert the food into muscle or meat. Thus, the antibiotic supplementation of poultry diet has numerous benefits.
Despite the advantages, the practice of supplementing poultry diet with antibiotics is increasingly problematic. Sub-therapeutic doses of antibiotics are linked to the increased presence of antibiotic-resistant bacterial strains in humans, animals and in the environment. It is also possible for residual antibiotics to appear in food that is meant for human consumption. To prevent residues, antibiotics are generally withdrawn from the feed of the poultry at least two weeks prior to slaughter to allow for drug clearance, and hence to prevent the antibiotics sequestered in the poultry from ingestion by humans.
Of particular importance to human consumers is Salmonellosis (Salmonella infection), associated with the pathogen Salmonella enterica subspecies enterica serovar Enteritidis (S. Enteritidis). Poultry products, including eggs and poultry birds, serve as a reservoir for S. Enteritidis. Poultry birds can be asymptomatic for Salmonella infection, thus making it difficult to isolate infected birds. The S. Enteritidis pathogen can pass to humans via contaminated poultry products through the food production chain. Undercooked or raw eggs and poultry meat thus constitute a high risk of infection for humans. In fact, poultry carcasses entering the processing environment are generally contaminated with bacteria such as Salmonella. 
As one example of an attempt to prevent the transmission of Salmonella to human consumers, ground turkey samples are routinely tested for Salmonella. For example, 25 gram samples of ground turkey are tested and 50% of the samples must be free of Salmonella. Recent outbreaks of food poisoning associated with ground turkey have prompted proposals to increase the standards for ground turkey, which with current production methods may greatly increase the number of samples testing positive for Salmonella. What is needed are improved antibiotic-free methods of treating poultry to reduce the incidence of Salmonella in poultry products.